ITRI CCL Switch Router Design Implementation Paul C

ITRI CCL Switch Router Design & Implementation Paul C. Huang, Ph. D. ITRI / CCL / N 300 pchuang@ccl. itri. org. tw CCL/N 300; Paul Huang 10/30/2020 1

ITRI CCL l Teaching Staff Lecturer » 黃肇嘉 (pchuang@ccl. itri. org. tw) – MIT Generalized Oversampled A/D Converter – U. Tokyo Multicast Routing Algorithms EECS BS / MS ‘ 87 EECS Ph. D. ‘ 94 – Bellcore Optical Switch / Optical Transceiver / High Speed Mux – CCL l LAN switching Teaching Assistant » 魏煥雲 (gis 87517@cis. nctu. edu. tw) » 張政賢 (chchang@cis. nctu. edu. tw) l CCL/N 300; Paul Huang Guest Lecturer » 王耀宗 Switch-Router Testing Methodology » 呂國正 Verilog Implementation of Routing function 10/30/2020 2

ITRI CCL Course Grading l l Assignment Load » 25% 3 sets of Homework assignments » 30% 2 sets of Labs » 15% Presentation » 30% Final Project Grading Policy » Quality, not quantity » Innovativeness » Late penalty (15% daily, including weekends & holidays). CCL/N 300; Paul Huang 10/30/2020 3

ITRI CCL Course Schedule l (2/24) Course Introduction - General communications network basics - Network market reality (success / failures) - Evolution towards Switch Router: Why, Where, When, and How l (3/3) The Basic Requirements of Switch Router - IEEE / IETF overview - Current System and IC product features & specification - Current IC product architecture l (3/10)Switch-Router Architectures - Switch architecture - IEEE 802. 3 (10/1000 Mbps MAC) - IEEE 802. 3 x l (3/17)Switch-Router Testing Methodology (王耀宗) - Lab I: CCL/N 300; Paul Huang L 2 Performance / Functionality Testing 10/30/2020 4

ITRI CCL Course Schedule l (3/24)Traffic Management & Implementation Issues and Pitfalls » Understanding Traffic Management (RSVP, Diff. Serv, Qo. S, Buffering, Routing, Scheduling) » Buffer Mgt l (3/31)Traffic Management & Implementation Issues and Pitfalls » Queue Mgt. » Scheduler l (4/7) Routing Implementation Issues and Pitfalls » Route Forwarding Techniques » Implementation Issues at Gbps » Example Implementation l (4/14)Verilog Implementation of Routing function (呂國正) » Lab II: CCL/N 300; Paul Huang L 3 Performance / Functionality Testing 10/30/2020 5

ITRI CCL Course Schedule l (4/21)Routing Algorithms - Basics of Routing - Classification of Current Routing Algorithms & Protocols (Unicast / Multicast) l (4/28)Implementing Unicast Routing Functions - Interior Routing Algorithms (RIP) - Interior Routing Algorithms (OSPF) - Exterior Routing Algorithms (BGP) l (5/5) Implementing Multicast Routing Functions - (Multicast Routing (DVMRP) - Multicast Routing (PIM) - Multicast Routing (CBT) l (5/12)Advance Routing Topics - ATM Routing Protocol (NHRP) - Policy-based / Co. S / Qo. S Route - Final Project: CCL/N 300; Paul Huang 10/30/2020 6

ITRI CCL Course Schedule l (5/19)Project presentation - (50 min / group): Total 3 groups. l (5/26)Project presentation - (50 min / group): Total 3 groups. CCL/N 300; Paul Huang 10/30/2020 7

ITRI CCL l Course Benefits Industry focus l » Market reality » English comprehension » Standards process » Interactive (hopefully) » Product concepts l Additional benefits l Knowledge focus Unfocused on … » Not presentation of protocols » Networking fundamentals » Not theoretical » Testing fundamentals » Not number crunching » Actual design trade-offs » Design concepts Thanks for being my guinea pigs CCL/N 300; Paul Huang 10/30/2020 8

ITRI CCL Teaching Philosophy Confucius (Eastern) Socrates (Western) Knowledge CCL/N 300; Paul Huang Knowledge 10/30/2020 9

ITRI CCL Network Engineering Why are you interested ? How is it different ? Is it your cup of tea? CCL/N 300; Paul Huang 10/30/2020 10

ITRI CCL IT • PC Motherboard • PC Manufacturer • Notebook Taiwan’s Industry PC Peripheral Data. Comm • • • Modem / NIC Add-on Cards (Graphics) Scanner / Digital Camera Monitor / LCD Monitor CPE Tele. Comm • Telephone • KTS • • • IC Design House • • Foundry CCL/N 300; Paul Huang 10/1000 NIC Dual Speed Hub L 2 Switch SOHO Router Wireless LAN x. DSL Modem Cable Modem Cellular Phone DLC / HDSL RAS Systems Integration • Switch-Router • DSLAM • Access Switch Software • • Internet Middleware OS Protocol Applications PC Chipset Network Chipset Consumer IC Memory LCD Opto-Electronics 10/30/2020 11

ITRI CCL l l Key Engineering Skills Telecommunications l » Scalability » Accuracy » Reliability » Speed » Completeness Data communications » Compatibility l » Reproducibility Information Technology » Manufacturing Cost l Mobile » Miniaturization » Logistics l Manufacturing Equipment » Flexibility » Standards conformance l Test Equipment » Low power Foundry » Manufacturing Cost l Wireless » SNR » Yield Process » Error recovery CCL/N 300; Paul Huang 10/30/2020 12

ITRI CCL Fundamental Engineering Skills l Theoretical » Mathematics / Physic » Algorithmic » Modeling l Design » Power » Analog Circuit » Digital Logic » Software » Architectural l CCL/N 300; Paul Huang Protocol 10/30/2020 13

ITRI CCL Key Engineering Value l Intellectual Property » Patents, copyright, trade secrets l Service Differentiation » Functional » Management l Content » Information » Knowledge CCL/N 300; Paul Huang 10/30/2020 14

ITRI CCL The Value Chain in Networking has Changed Chips Software Chips System Design & Integration Software System Manufacturing Distribution Already Happened in the PC Business • Intel makes the chips; Microsoft makes the software. • Dell and Compaq focus on manufacturing, relentless cost cutting, and distribution, not R&D • Little system-level innovation, few new system startups • Plenty of silicon innovation; plenty of silicon startups • Shift from managing scarcity to creating abundance CCL/N 300; Paul Huang 10/30/2020 15

ITRI CCL Porter’s Industry Attractiveness Model Threat of Competitor Customer Power Industry Attractiveness Supplier Power Threat of New Entrant CCL/N 300; Paul Huang 10/30/2020 16

ITRI CCL Product Line of Ethernet LAN IC IP MAC PHY NIC 3 in 1 PHY Single PHY 2 in 1 Single Speed Hub 3 in 1 Dual Speed Hub 3 in 1 Octal Port Switch 8 +1 Layer 3 Switch Quad Port Gigabit Layer 3 Switch 8 +1 Layer 2 Switch Quad Port Gigabit Switch Quad PHY TXVR Transceiver 10 Mbps CCL/N 300; Paul Huang Dual Port Switch Hub Contr. . Octal Port Layer 3 Switch 100 Mbps 10/30/2020 1000 Mbps 18

ITRI CCL Network Technology Creating abundance Velocity of change CCL/N 300; Paul Huang 10/30/2020 19

ITRI CCL Technology Pace has Exploded Technology Applications Transistor IC /Processing CPU DSP Chips/ Lithography Technology IC Design (Spice Modeling) 2 DAnalog / 3 D Graphics Engine Memory (Rambus) LCD Displays A/D Conversion 10 Computing / 1000 Technology Ethernet DSP Algorithm Multi-Layer Ethernet Switch Digitization x. DSL (G. Lite, ADSL, VDSL, etc. ) Software Technology Cable Modem Technology Creation Explosion Terabit Switch-Routers Dense WDM Technology Networking Packet / Cell Switching Focus. Fiber on Technology Innovation, Optical / Laser Technology Not. Science Technology Invention Material CCL/N 300; Paul Huang 10/30/2020 20

ITRI CCL l Technology Creating Abundance Chips for networking have twice as many gates every 18 months, thanks to Moore’s Law. » We can build network systems on a chip for minimal incremental cost or “free”. » We can pack billions of DSP ops/sec on a chip. We » We can route 10 s of millions of packets/sec on a chip. l Optics performance doubles every 12 months. Twice as many wavelengths on the same fiber every year. Eventually, that changes everything. l Packet switching (IP) is taking over everywhere. Fundamental packet technology performance is doubling every 12 months, outpacing alternatives. CCL/N 300; Paul Huang 10/30/2020 21

ITRI CCL Moore’s Law Meets Network ICs ä Cost is dropping to $15/port ä Full L 3 and L 4 routing, Qo. S, accounting, etc. “for free” ä New standards like Diff. Serv, RSVP, H. 323, IPsec, can all be handled with the same chips at the same cost $45 $40 $35 Total Bill of Materials for 10 K boxes/month $30 $25 $20 $15 $10 End’ 97 Mid’ 98 End’ 98 L 2 through L 7 Mid’ 99 Managed L 2 Source : MMC networks CCL/N 300; Paul Huang 10/30/2020 22

ITRI CCL DWDM: A Breakthrough Technology 300 Doubling Each Year: 2000: OC-192, 80 l 2001: OC-192, 160 l 250 2002: OC-192, 320 l OC-192, 32 l OC-48, 96 l 200 OC-192, 16 l 150 OC-48, 48 l 100 1. 7 OC-192, 4 l 8 4 C- O OC-192, 2 l CCL/N 300; Paul Huang 10/30/2020 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 1985 1983 1982 0 1999 56 5 M ps b G 1998 bp 1997 s bp 5 M 3 1 1986 s 50 1984 System Capacity (Gbps) 350 23

ITRI CCL Demand Growing Faster than Technology Basic technology Performance doubling time Moore’s Law -gates/chip 18 months; 59% / yr. Optical fiber - bps/fiber 12 months; 100% / yr. Packet switching - $/bps 12 months; 100% / yr. Basic demand Traffic doubling time Internet users 12 months; 100% / yr. Data bits 7. 5 months; 300% / yr. Internet core 4 months; 1, 000% / yr. CCL/N 300; Paul Huang 10/30/2020 24

Changing of the Era: SONET WDM ITRI CCL The SONET Era The WDM Era l “Free” local calls, expensive long distance l Expensive access to “free” backbone l Circuit/TDM model l Packet model l Transmission was king; efficiency was key. l Switching is king; features are key l Service was based on multiplexing l Service is based on internetworking l Data used existing transmission l Data demands new transmission l Few, legacy carriers with legacy nets l Thousands of new carriers with new nets l Managing scarcity l Creating abundance CCL/N 300; Paul Huang 10/30/2020 25

ITRI CCL Changing of the Era: Network Processor Original Assumptions New Assumptions l IP routing is based on destination address l Can route on SA, DA, port, URL, DS types, etc. l Routers can maintain only a few queues per port l Routers can have tens of thousands of queues l Fast switching must be very simple l Chips can be application-aware, still run at many Gbps l Signaling, traffic management should be done only at call setup l Its possible to do shaping, policing, WFQ, NAT, tunneling for each packet l Very fast switching requires fixed length cells l It is no harder to switch a packet than a cell l Cell and frame networks are very different l In hardware, cells and frames are interchangeable. CCL/N 300; Paul Huang 10/30/2020 26

ITRI CCL Changing of the Era: Packetization This transition is as fundamental as the shift from analog to digital CCL/N 300; Paul Huang 10/30/2020 27

ITRI CCL Changing of the Era: Service Networks Telco Business Model Internet Business Model l Regulated monopolies l Unregulated providers l Protected local / domestic markets l Global market with global competitors l High barriers to entry l Low barriers to entry l Pricing based on usage l Pricing based on access l Smart network l Stupid end devices l Smart end devices l Profits generated by managing scarcity l Profits generated by creating plenty CCL/N 300; Paul Huang 10/30/2020 28

ITRI CCL Network Service Paradigm Shift New business model CCL/N 300; Paul Huang 10/30/2020 29

ITRI CCL Biggest Driving Factor: Internet Traffic Growth assumes more real-time services including multicast Users (Millions) Usage Sizes (KB) Annual Packet Traffic (Billion Packets) 5000 100 -500, 000 -2 4, 00 0 40 x 5, 0 0 0 x 0, 00 0 x 200 35 5 1990 1 1995 * ** ** 2000 e E-Mail 50 25 Web, Video Home-Page Infomercial Surfing** Usage*** 1990 1000 1995 2000 e Presumes growth in PC-installed base from 1995’s 60 million to 2000’s 475 million 5 KB/page x 10 Web pages per user 500 KB/seconds x 10 seconds Source: IDC, Zona Research, Literature Searches, Team Analysis CCL/N 300; Paul Huang 10/30/2020 30

ITRI CCL/N 300; Paul Huang Internet’s Exponential Growth & Changes 10/30/2020 31

ITRI CCL The Current PSTN Model Potential Competitors Baby Bells, GTE Connectionless Signaling Network SS 7 4 ESS, 5 ESS Thin Clients CCL/N 300; Paul Huang Connection-Oriented Bearer Network 10/30/2020 32

ITRI CCL The Current Internet Model Potential Competitors 1000’s ISPs, Telcos, Hi. Net IP Routers Thick Client SONET, ATM CCL/N 300; Paul Huang Connectionless Bearer Network 10/30/2020 Connection-Oriented Transport Network 33

ITRI CCL A Possible Future Model Potential Competitors AT&T (@Home), World. Com (UUNet), AOL, Direct. PC Internet Connectionless Signaling Network Thick Client SS 7 -Aware Gateway Future Nets Connection-Oriented Bearer Network • Application Specific • VPN Capable Thin Clients CCL/N 300; Paul Huang 10/30/2020 34

ITRI CCL Another Possible Future Model Potential Competitors Qwest, Level 3, Delta Three, Concentric, IDT, Bigger Faster Internet Thick Client SS 7 -Aware Gateway Connectionless Signaling Network & Best-effort Data Delivery Connection-Oriented Services: • IP Telephony • VPN Capability • Assured Data Delivery Thin Clients CCL/N 300; Paul Huang 10/30/2020 35

ITRI CCL Network Architecture Conventional Voice (PBXs & phones) Enterprise Protocol IP / IPX / SNA Enterprise Transport Ethernet ATM / FDDI / TR Analog IP / ATM Frame Relay Access: Protocol Users want choice and interoperability Access: Physical Applications provide Internet. Access provides the Network Intelligence Edge. Services Cable x. DSL / ISDN SONET / SDH Satellite / Wireless Core Tele. Comm / Cable / Wireless provides the Access and the Transport CCL/N 300; Paul Huang 10/30/2020 36

ITRI CCL Network Convergence Video Voice Core SNA TDM RAS Wireless Voice Data Service Specific Vertical Integration from Access to Core EDGE • Deregulation • Technology • The Internet • Global Commerce Voice Core Data ISDN Data FTTx Core HFC Frame Relay EDGE IP ATM Copper VPN Video Intranet Data Any access technology on a Common Edge/Core Architecture offers great flexibility while reducing cost CCL/N 300; Paul Huang 10/30/2020 37

ITRI CCL Service & Content Revenue Trends Private Services Public Services Content Functional Differentiation Quality and Cost Managed Intranets Electronic Commerce VPN Services Internet Services Increasing Value Frame Relay, Cell Relay Leased Line Services 7% 3% 10% 1997 20% 25% 30% 45% 2000 25% Relative income from basic services decreasing - value added services key to profitability CCL/N 300; Paul Huang 10/30/2020 38

ITRI CCL The new business driver. . . THE CUSTOMER Regulated Environment IP/ATM Services Standards Bodies Manufacturers Service providers ISDN Customers New Competitive World The market, not regulators decide on standards today CCL/N 300; Paul Huang 10/30/2020 39

ITRI CCL Market Success / Failures Why do some succeed & some fail ? CCL/N 300; Paul Huang 10/30/2020 40

ITRI CCL Networking : A Technology Timeline Novell demonstrates first networked PC LAN Robert Metcalfe found 3 Com 1969 1973 1979 1981 1982 Robert Metcalfe and David Boggs build first Ethernet; 2. 944 Mbps over coax 3 Com ships first 10 Mbps Ethernet adapter; $950 CCL/N 300; Paul Huang IBM introduces 16 Mbps token ring adapter IBM announces 4 Mbps token ring $830 per node Arpanet opens; 50 kbps, 4 hosts 1983 1985 Fore and NET/Adaptive, among others, announce first ATM switches; roughly $5000 per port IETF established 1986 1987 1988 Cisco ships AGS router IEEE approves 802. 3 Ethernet Synoptic ships first Ethernet hub 10/30/2020 1989 Frame Relay Forum founded ATM Forum established 1990 1991 1992 Sun introduces Iava Bay Networks established 1993 1994 1995 1996 Ipsilon Networks ships IP switching Kalpana ships first Ethernet switch; $1450 per port IEEE splits work on fast Ethernet into two groups, 100 Base-T and 100 VG Alteon demos first gigabit Ethernet switch and adapter 41

ITRI CCL Market Tradeoffs Cost Functionality Time to Market Winner == Right Product at the Right Time at the Right Cost CCL/N 300; Paul Huang 10/30/2020 42

ITRI CCL Strategies and Corresponding Value Propositions Market Segment Vendor-Created Market-Created 1 Innovative Product Replicative CCL/N 300; Paul Huang 3 Evolution Breakthrough 2 4 Differentiation Reposition 10/30/2020 43

ITRI CCL Broadband Network Market Application CPE Data. Comm provides Network Intelligence Department Corporate SBU Division Enterprise Networking Internet Backbone SOHO Networking RAS (Copper, Cable) SONET / DWDM CO / Cable Tele. Comm / Cable / Wireless provides the Access and the Transport CCL/N 300; Paul Huang 10/30/2020 44

ITRI CCL/N 300; Paul Huang LAN vs. WAN 10/30/2020 45

Bridge vs Router ITRI CCL Need more Functionality (VLAN, Multicast, Routing, etc. ) Ethernet Switch Available Approaches Bridge Router • Big Fast Router • Layer 3 Switch Router • IP Forwarding Switch • MPLS / IP Switch • ATM Switch Need for Lower Cost, Higher Bandwidth • ? ? ? “ASICs are the technology enabler. Like the introduction of the microprocessor, new chips will revolutionize the networking industry. ” -- David House (Chairman, President, and CEO of Bay Networks) CCL/N 300; Paul Huang 10/30/2020 46

ITRI CCL LAN Standards IEEE 802. 2 LLC MAC 802. 3 802. 4 802. 5 802. 6 802. 11 802. 12 802. 14 ANSI Token Passing Ring Dual Bus Distributed Queue Wireless CSMA /CD Token Passing Bus Demand Priority Cable TV FDDI I & II LAN Public LAN CCL/N 300; Paul Huang LAN Data Link Layer PHY 10/30/2020 LAN WAN Campus 47

ITRI CCL High Speed Networking IP Ethernet Frame Switch Gigabit Ethernet Backbone IP Edge Hub IP Ethernet Frame Cell IFMP, GSMP, TDP IP Cell Switch IP Switch Backbone ATM Edge Hub IP Ethernet ATM Frame Cell IPOA, LANE, MPOA ATM Cell Switch ATM Switch Backbone CIF Edge Hub ATM Frame Cell ATM Cell Switch ATM Switch Backbone 10 / 100 Ethernet Access ATM Edge Switch CCL/N 300; Paul Huang 10/30/2020 48

ITRI CCL/N 300; Paul Huang IP Switching Model Integrated Routing 3. Multi-Layer Switching Model (Tag Switching, MPLS) 2. Integrated Model (IP Switching) Layered Routing 1. Overlay Model (MPOA) Simplified addressing, Separate routing (NA) Subnet Addressing Peer Addressing 10/30/2020 49

ITRI CCL A Taxonomy of IP Switching Solutions IP Switching Peer Overlay Layer 3 Switch Flow Topology Flow Address Resolution Layer 4 Switch IFMP/GSMP Tag Switching MPOA Classical IP Gigabit Routers CSR/FANP ARIS LANE Terabit Routers IP Navigator NHRP Qo. S Router VNS MARS MPLS RFC 1483 PVC ä Different environments warrant different solutions ä Factors : scalability, cost, simplicity, extensibility, etc. CCL/N 300; Paul Huang 10/30/2020 50

ITRI CCL Club Sandwich Debate (Protocols) Demand for Internet applications, plus new packet technologies VCs for flows, VPNs, Traffic engineering. IP Very Uneasy Match ATM Provides reliability, provisioning SONET WDM Very Simple Match Provides cost breakthroughs in bandwidth. CCL/N 300; Paul Huang 10/30/2020 51

ITRI CCL l Other Success & Failure Physical Interface l » Modems / ISDN / x. DSL / Cable Modem » OSI vs TCP/IP » ATM Forum vs IETF – 25. 6 Mbps, TAXI, SONET/SDH l l Network Architecture Other famous battles » Wintel vs. Macintosh » DLC » VHS vs Beta » HFC l » FTTC / FTTH l Protocol Battles to come » Terabit Cell vs Terabit Packet switch WAN Protocol » Frame Relay » SMDS » ATM l Network Management » SNMP vs CMIP CCL/N 300; Paul Huang 10/30/2020 52

ITRI CCL Key to Success l An innovation is adopted more quickly if: » Big Payoff: It shows an easily measured advantage relative to existing methods, through low cost or great results. » Investment Protection: It can be adopted compatibly, without having to discontinue or discard the old approach. Often by eliminating architectural changes and protocol development – – Simpler interoperability — plug & play Easier adoption — mix & match Faster time to market — no waiting for standards Greatly reduced complexity » Low Risk: It lends itself to initial small-scale implementations CCL/N 300; Paul Huang 10/30/2020 53

ITRI CCL Fast Ethernet is a Winner 100 Mbps Ethernet 1. Big Payoff ? Yes -- 10 fold speed-up for little or no cost 2. Investment Protection ? Good -- and 10/100 chips enable a mix and match installation 3. Low Risk ? Yes -- very low cost, can be adopted incrementally, can be sensed automatically CCL/N 300; Paul Huang 10/30/2020 54

ITRI CCL Frame Relay is a Winner Frame Relay 1. Big Payoff ? Yes -- Good price / performance vs. private lines 2. Investment Protection ? Excellent -- just a software upgrade to most boxes 3. Low Risk ? Yes -- very low cost, can be adopted incrementally, can grow to large size / high speed CCL/N 300; Paul Huang 10/30/2020 55

ITRI CCL Multi-Layer Switch will be a Winner Multi-Layer Switch 1. Big Payoff ? Yes -- 10 X performance for 1/10 th the cost 2. Investment Protection ? Excellent -- works just like a router, only faster 3. Low Risk ? Yes -- very low cost, can be adopted incrementally, can grow to large size / high speed CCL/N 300; Paul Huang 10/30/2020 56

ITRI CCL Network Backgrounder Introduction to various network devices IP Switching Tag Switching CCL/N 300; Paul Huang 10/30/2020 57

ITRI CCL Today’s Dominant Network Model B B l Routers (Pros) R R l » Broadcast Firewalls » Dynamic Path » Security l Routers (Cons) » » » CCL/N 300; Paul Huang H H R Bridges / Switches (Pros) » Plug & Play connectivity » Simplicity » Performance l Bridges / Switches (Cons) » » Protocol dependence Application fairness Performance Administrative Complexity Scalability 10/30/2020 Broadcast storms Bandwidth intensive for WAN Static Path Scalability 58

Evolving Networking Architecture ITRI CCL l Bridged network » Microsegmentation l Collapsed backbone routers » Use a router to tie shared-media or switched LAN segments together l Switched network » Hierarchical network l VLANs with “one-armed” routers » Used to contain broadcast to within one VLAN. » Just like subnets, VLANs are interconnected by routers, except that routers link virtual LANs, not physical LAN segments, leading to the “one-armed” configuration of the router hanging off a switch. » Focused on “switch when you can, route when you must” strategy. CCL/N 300; Paul Huang 10/30/2020 59

Evolving Network Architecture ITRI CCL l Cut-through routing » Use route servers + “cut-thru” techniques to avoid the need to detour all intersubet traffic through “one-armed” router bottlenecks, thereby improving network efficiency and performance. » Focused on “route once, switch many” strategy. l Gigabit Wirespeed Routing in Hardware » Use the latest ASIC technology to perform routing in specialized hardware. » Focused on “route whenever you need to” without any performance penalties or the need to create multiple VLAN network overlays. CCL/N 300; Paul Huang 10/30/2020 60

ITRI CCL “Best Effort” “Guaranteed” Next Generation Network Datagram l Base Technology Integrated l » Switch-Router l Protocol Routing Hops l Pros l l l Protocol » ATM + rest Routing Hops l Pros » Guaranteed Qo. S » Virtual networking » Multi-service Cons » Non-standard Routing Hops » 0 or 1 » Looks like a router & performs like a switch Cons » Scalability l » ~ 2+ » It’s a router l Protocol Base Technology » ATM Switch » IP » Many l l » ATM Switch » IP / IPX l Base Technology Overlay l Cons » Complexity » Forklift upgrade CCL/N 300; Paul Huang 10/30/2020 61

ITRI CCL l The “Datagram” Model “Router-based” Networks » Routers are always in the datapath running common routing protocols » All services (Routing, IP Multicast, Co. S, etc. ) are performed by routers. » Latency = n( # hops, services, … ) = independent forwarding decision for each packet l Future Enhancements » IP forwarding switch, Layer 3 switches, Layer 4 switches, Multi-layer switches » Gigabit Switch Routers, Terabit Switch Routers (Tiny Tera) Performance is optimized within a device; best-effort delivery CCL/N 300; Paul Huang 10/30/2020 62

ITRI CCL Historical Issues with Datagram l IP only » Doesn’t support multi-service (ATM, Frame Relay) l Only “Best Efforts” » Shared Qo. S = no Qo. S » Router-based RSVP not scalable » Too much latency for real time data delivery l Traditionally, router bandwidth is limited l Doesn’t support traffic engineering But: Many of these issues are being corrected CCL/N 300; Paul Huang 10/30/2020 63

ITRI CCL The “Overlay” Model S E S S S l S S One-arm Router “Overlay-Model” Networks » End-to-end / Edge-to-edge switching model » Routing is performed only on connection setup » Centralized control via some kind of server – either to translate addresses or to provide routes – limits the cost and complexity of edge devices – IETF Standards: – ATM Forum: NHRP, MARS LANE, MPOA Performance is optimized end-to-end; Guaranteed Qo. S delivery CCL/N 300; Paul Huang 10/30/2020 64

ITRI CCL l The “Overlay” Model — Pros & Cons Provides a lot of benefits » Potentially better latency (Qo. S), performance (Throughput), and scale (Size) » Virtual overlay allows new services to be added without penalty – Multi-Service – Virtualization (LANE, VPNs) » Traffic Engineering l But » If full “n 2 -squared” connectivity, limited scalability (in size) » If partial connectivity, multiple hops may be needed across backbone CCL/N 300; Paul Huang 10/30/2020 65

ITRI CCL l The “Overlay” Model — Edge-to-edge Advantages l » Runs existing legacy routing protocols over ATM (OSPF, IS-IS, RIP, etc. ). Disadvantages » Legacy routers have imperfect topology information about the ATM network: – An ATM net is not a single broadcast LAN. » Offers investment protection and risk avoidance for existing networks. – It is not a single link or N 2 links among all routers or just selected links. » Uses familiar and mature technology. – It is more than just emulated LANs. » Segregates router implementation from ATM implementation. – Multiple ATM hops may be needed across backbone. » Routers have no existing software for SVCs. » Is a reasonable approach for campus backbones. » Suboptimal; no end-to-end Qo. S. » Server-based solutions raise scalability problems. » The Internet needs a different solution. CCL/N 300; Paul Huang 10/30/2020 66

ITRI CCL The “Integrated” Model S S S l S “Integrated-Model” Networks » Routers are always in the edge of the network » Switches are always in the core of the network » Tags are used to identify the services required of the network » Latency constant l Future Enhancements » Ipsilon IP switch, Tag Switch, ARIS, Fast IP, etc. » MPLS standardization completion CCL/N 300; Paul Huang 10/30/2020 67

ITRI CCL Addressing Schemes There are 2 Alternatives for Addressing ATM Switches and Routers » Peer model: – The ATM address is treated as a logical internetwork layer address. – An algorithm can translate between IP and ATM addresses. – Internetwork routing done in ATM switches, which have IP addresses. » Subnet or overlay model: – ATM and internetworking use separate address spaces (chosen by the ATM Forum). – An address resolution protocol is needed. – This decouples the efforts of the Forum and IETF. CCL/N 300; Paul Huang 10/30/2020 68

ITRI CCL Routing Schemes There are 2 Ways for ATM Switch Routing to Work with Internet Routing. » Layered routing: – Conventional Internet routing runs over ATM routing. – Usually involves route or address servers. » Integrated routing: – ATM routing is used to support internetworking directly, or there is only one algorithm. – One choice: have the ATM switches run IP routing protocols. – Another choice: have the ATM switches use forwarding tables set up in advance by the IP routers. ¤ Note that this choice is independent of the choice of peer or subnet addressing CCL/N 300; Paul Huang 10/30/2020 69

ITRI CCL Gigabit Ethernet What it use to be ? What it has become. What is the key ? CCL/N 300; Paul Huang 10/30/2020 70

ITRI CCL l Ethernet - what it used to be. . . Shared Ethernet l » low cost of integration » CSMA / CD – homogeneous – interoperability – backward compatible » 10 Mb/ s » Half Duplex » longevity & future proof » Distance Limited l » Shared Bandwidth Ease of Management » low operations & maintenance cost » Latency Under Heavy Loads » minimal hidden cost » Lack of Priority Mechanism l » Lack of Bandwidth Management CCL/N 300; Paul Huang Ease of Installation Cost » 2 X ~ 3 X cost for 10 X performance 10/30/2020 71

Ethernet - where it is going. . . ITRI CCL l Multiple Data Rate Options » 10 Mbps, 1000 Mbps (IEEE 802. 3 z Gigabit Ethernet) » Full Duplex Option (IEEE 802. 3 x) » Trunking (Cisco’s Etherchannel) » 10, 000 Mbps soon thereafter? l No Distance Limitations related to CSMA/CD or Data Rate » Media determines distance in Full Duplex l Latencies Are Coming Down » Very low insertion delay in Gigabit Ethernet – 0. 5 microsec for short frames – 12 microsec for longest frames » Very low switch latency in multi-Gigabit switches – Under 10 microsec – As low as 3 microsec CCL/N 300; Paul Huang 10/30/2020 72

Ethernet - where it is going. . . ITRI CCL l Switched Ethernet Is The Norm » Mix of 10/1000 Mbps ports in same box » Switching capacities in the tens of Gigabits/sec – Historically, ten-fold capacity increase every two years » Cost per switched Mbps coming down – Historically, prices dropped to 1/2 or 1/3 every two years l Scalability and Fault Tolerant Topologies » Area of emphasis in new generation of switches » Aggregation of traffic on multiple ports CCL/N 300; Paul Huang 10/30/2020 73

Ethernet - where it is going … ITRI CCL l Ethernet Switches Have Multiple Queues » Priority of packet determines latency » IEEE 802. 1 p, IETF ISSLL l Bandwidth Management Added » Flow Control specified in IEEE 802. 3 x – XON / XOFF – Switch to Switch, or Switch to End-node Signaling » Virtual LANs specified in IEEE 802. 1 q – Frames are tagged to indicate VLAN association – Switches interpret the tags and create campus- wide. VLANs » Advanced Filtering IEEE 802. 1 p - Multicast – Protocol defined for dynamic registrations / deregistration for multicast session - GARP/ GMRP (802. 1 p) and GVRP (802. 1 q) CCL/N 300; Paul Huang 10/30/2020 74

Networking - where it is going … ITRI CCL l Layer 3 Routing capabilities » Wire-speed routing » Performance points as high as 100 X relative to traditional routers » Eliminates the complicated “route once, switch many” » Qo. S routing l Layer 3 Bandwidth Mgt. » RSVP » SBM » Co. S (Class of Service) » Policy-based Qo. S – – CCL/N 300; Paul Huang Qo. S Policies set centrally by network administrator Network flows identified in real time No changes required at the end station No changes required to the applications 10/30/2020 75

Networking - where is it going. . . ITRI CCL l Layer 4 switching » Flow based switching: A flow is a stream of packets exchanged between two (or more) users for any application. » Flows can be established with RSVP, CLI or SNMP » Allows route engineering and service differentiation, facilities that ISPs need and love to have. » Allows fine- grained traffic control and enterprise wide policy controls CCL/N 300; Paul Huang 10/30/2020 76

Networking - still to come ITRI CCL l End-to-End Standardized Congestion Management » Beyond 802. 3 x Flow Control l “Contract based” Guarantees on » Latency Variation / Jitter » Available bandwidth l Security » Firewall » SYN attack prevention CCL/N 300; Paul Huang 10/30/2020 77

Network - standards status ITRI CCL l IEEE Standards » IEEE 802. 3 x - Standard in 1997 » IEEE 802. 3 z - Standard in Q 3 1998 » IEEE 802. 1 p - Standard in Q 2 1998 » IEEE 802. 1 q - Standard in Q 3 1998 l IETF Standards » ISSLL - Integrated Services Over Specific Link Layers – IS to IEEE 802. 1 p service mappings – Layer 2 Ethernet switches will be able to participate in call-admission control and traffic policing » IGMP for Next Generation of Layer 2 Ethernet Switches CCL/N 300; Paul Huang 10/30/2020 78

So, is this still Ethernet ? ITRI CCL l Preservation of the Ethernet Frame Format is Key » Allows backward compatibility » Enables high performance low cost switching (no need for frame translations or segmentations) » Best fit to what is on the majority of desktops l Other Than the Frame Format. . . » It certainly is very different from the original 10 Base 5, coax based, shared, CSMA/ CD Ethernet! l It is Winning Because. . . » We got here through a series of pragmatic, reality based, improvements (that took 17 years) » Successful technologies are not about perfection, but about compromise between complexity, performance, ease of deployment and cost CCL/N 300; Paul Huang 10/30/2020 79

ITRI CCL IP Switch CCL/N 300; Paul Huang 10/30/2020 80

IP Switch -- Concept ITRI CCL IP Switch Gateway SYSTEM STATUS ITRI Ethernet to ATM Switching CCL Hub ---------------------EAS - 3000 POWER RUN/DIAG . . . ATM STATUS LINE DETECT Rx SIGNAL Tx Rx LE Tx A 2 E E 2 A Ipsilon Flow Management Protocol IP Switch Controller IP Switch Gateway Ipsilon Flow Management Protocol SYSTEM STATUS ETHERNET STATUS ITRI . . . P 1 P 2 P 3 P 4 P 5 P 6 P 7 P 8 Rx Tx COL Ethernet to ATM Switching CCL Hub ---------------------EAS - 3000 General Switch Management Protocol POWER RUN/DIAG . . . ATM STATUS LINE DETECT Rx SIGNAL Tx Rx LE Tx A 2 E E 2 A ETHERNET STATUS. . . P 1 P 2 P 3 P 4 P 5 P 6 P 7 P 8 Rx Tx COL ATM 155 Mbps ATM Switch CCL/N 300; Paul Huang 10/30/2020 81

IP Switch -- Configuration ITRI CCL IP switching Ignores all of the ATM Forum Software Applications IP Software ATM Forum Software IP Software MAC Layer Transport ATM H/W IP Switching combines the best of IP software and ATM H/W CCL/N 300; Paul Huang 10/30/2020 82

Ipsilon Protocols ITRI CCL ATM IP Switch Controller GSMP Upstream Node IFMP ATM Switch IFMP - Ipsilon Flow Management Protocol r r r IFMP GSMP - General Switch Management Protocol between multiple IP Switches or hosts Less than 10000 lines of code Protocol used to send flow redirection messages r r r CCL/N 300; Paul Huang Downstream Node 10/30/2020 Simple protocol that provides call setup, tear down & call status Less than 2000 lines of code Capable of operating with any ATM Switch 83

Flow vs. Connection Oriented Traffic ITRI CCL l l A Flow is a sequence of packets sent from a particular source to a particular destination that are related in terms of their routing and any local handling policy they may require It performs a similar function in a connectionless network to the role the connection plays in a connection oriented network. m m m Two packets belong to the same flow if the type of service, protocol, source/destination addresses/ports are the same. short-lived traffic is ideal forwarding long-lived flows are ideal for "cut-through" switching CCL/N 300; Paul Huang 10/30/2020 Flow-Oriented Traffic JFTP data JTelnet JHTTP JWeb Image downloads JMultimedia audio/video Short-lived Traffic CName Look-ups (DNS) CSimple Mail - SMTP CPOP CSNMP 84

IP Switch Operations ITRI CCL ATM IP Switch Controller (IFMP) Upstream Node Œ (vpi/vci = 0/15) Downstream Node ATM Switch Upstream Node ATM IP Switch Controller GSMP (IFMP) Upstream Node CCL/N 300; Paul Huang ATM Switch Downstream Node 10/30/2020 Upstream Node ‘ ATM Switch ‘ Downstream Node 85

IP Switch--Campus, Departmental Backbones ITRI CCL Direct Attached Servers IP Switch of Departments Ö Very-high IP throughput Ö Gbps of switching performance with IP routing functionality Ö Complements existing routed networks and LAN switching Ö IP Gateway used for LAN connection Ö Supports direct attached ATM servers IP OC-3 Switch OC-3 IP OC-3 10 Mbps 100 Mbps CCL/N 300; Paul Huang IP Switch Gateway OC-3 IP Switch Gateway 10 Mbps 100 Mbps IP Switch Gateway 10 Mbps FDDI Conventional Router 100 Mbps 10/30/2020 86

ITRI CCL l IP Switching Approach » Flow-driven IP switching » Integrated routing and switching » per-flow classification and mapping to establish dynamic shortcut paths CCL/N 300; Paul Huang 10/30/2020 87

ITRI CCL l Stated Advantages of IP Switch Simplicity, Flexibility, and Robustness of IP » Discards the complexity of ATM protocols (signaling, new routing protocol, new addressing scheme, LANE, MPOA, etc. ) » Uses well known, well debugged, and heavily tested standard IP routing » Backward compatible to existing network and network mgt. tools l Scalability and Speed of Switching » Uses flexible, scalable ATM hardware whose cost are decreasing rapidly » Allows connection-less and flow-oriented traffic » Functions like a traditional router, except 4. 5 times faster throughput » Supports Qo. S capability for future RSVP compatibility » Support multicast functionality for future IP multicast services CCL/N 300; Paul Huang 10/30/2020 88

ITRI CCL Potential Disadvantages of IP Switch l RSVP may not be as simple or low cost » still requires massive changes to the network (new adapters, new switches, new routers); (new softwares [ODI, NDIS, Winsock 2. 0, etc. ]) » Qo. S guarantees by RSVP is only a subset of ATM’s – Only nrt-VBR – No CBR, rt-VBR, ABR » Requires signaling (similar to Q. 2931? ) » Requires new routing protocols (not available yet) » RSVP is not ready; 2 ~ 3 years behind ATM CCL/N 300; Paul Huang 10/30/2020 89

ITRI CCL MPLS (Tag) Switch CCL/N 300; Paul Huang 10/30/2020 90

MPLS (Tag) Switching Overview ITRI CCL Tag Distribution Protocol Tag Switches (ATM Switch or Router) Tag Edge Router CCL/N 300; Paul Huang Existing Routing Protocol 10/30/2020 91

ITRI CCL/N 300; Paul Huang MPLS (Tag) Switching Example 10/30/2020 92

ITRI CCL Cell Interleaving Problem l Solution 1: » Use different VPI for each label space and different VCI to maintain source identity (unique VCI range for each ingress node) » Limited scalability to 4096 unique VPI labels l Solution 2: » VC Merging CCL/N 300; Paul Huang 10/30/2020 93

ITRI CCL l MPLS (Tag) Switching Tag Approach: » Topology-driven, not traffic-driven » No connection setup; prepopulate tags, distributed before traffic arrival » Map IP traffic to a switched path via control protocol information » Enhanced forwarding performance via label-swap paradigm » Generalized for any media encapsulation: ATM, FR, PPP, etc. » Agnostic to network layer services: allows any number of different network-layer functions to map to a simple and fast forwarding mechanism – Leverages existing routing protocol – Multiprotocol: IPv 4, IPv 6, IPX – Allows future features CCL/N 300; Paul Huang l Diffserv, RSVP, IP Multicast l Co. S / Qo. S Routing, Policy-based Routing 10/30/2020 94

ITRI CCL l MPLS (Tag) Switching — Pros & Cons Advantage » Combines L 3 flexibility & scalability w/ L 2 performance and traffic management – Internal routing flexibility (OSPF) – External routing scalability (BGP) » Log(n) scalability » Existing ATM networks – Allows IP to integrate with ATM – Integrated multi-service networks – Reduce complexity due to multiple peer router networks – Co-exist with ATM protocols or eliminate them all together l Potential Problem » Loop creation due to topology changes – Forwarding loop formed at L 2 goes undetected by L 3 loop mitigation mechanism – Lack TTL field in an ATM cell header. consumes both link and TSR resource CCL/N 300; Paul Huang 10/30/2020 95

ITRI CCL l Potential Refinements to MPLS » Two-level or multi-level tags can be pushed onto a stack, and popped off as the packet travels. » Explicit routes can override destination-based routing for Qo. S or traffic engineering. » Flow-driven short cuts can be used at the edge, with topology-driven short cuts in the core. l Tags or Labels can have Varying Granularity » A tag represents a forwarding equivalence class. » Fine granularity, for example: – One class per address prefix in routing table or per source-destination pair » Medium granularity, for example: – One class for each output port in the network or for each Web URL » Coarse granularity, for example: – One class for each node in the network or for each external network CCL/N 300; Paul Huang 10/30/2020 96

ITRI CCL Route Accelerator CCL/N 300; Paul Huang 10/30/2020 97

ITRI CCL Router Accelerator IP Forwarding Switch Router CCL/N 300; Paul Huang 10/30/2020 98

ITRI CCL Route Accelerator — Advantages *No Infrastructure Impact No new protocols *Implementation Cost A little higher than LAN switch *Reduced Price 1/10 th of router price *Increased Performance 10~20 x Boost *Maximum Scalability Routing protocols - not Spanning Tree CCL/N 300; Paul Huang ($500 vs. 5, 000/100 M port) 10/30/2020 99

ITRI CCL Learning/Forwarding in IP Forwarding Switch Learning: packets from router ports Forwarding: packets from network ports and router ports Network Ports Router Ports CCL/N 300; Paul Huang IP Forwarding Switch Router 10/30/2020 100

ITRI CCL Sending IP Packets Host 1 Inter-Subnet Router Int r a-S ub ne t Host 2 r Intra-Subnet Communication í Test under Mask is “true”. í Next hop’s address is exactly the destination MAC address. r Inter-Subnet Communication í Test under Mask is “false”. í Next hop’s address is the router’s MAC address. CCL/N 300; Paul Huang 10/30/2020 101

ITRI CCL An Example of Inter-Subnet Communication to destination IP: BB Test under Mask: false (ARP_Req) 1 2 3 4 Network Ports FF aa aa AA ? ? RR DA 2 SA 2 source Ethernet address (SA 3) source IP address (SIP) destination Ethernet address (DA 3) destination IP address (DIP) HOST ARP cache IP MAC BB rr CCL/N 300; Paul Huang IP BB port 4 FF aa aa AA ? ? RR port 4 cc rr AA BB MACsub port cc Router Ports port 4 rr aa (IP Pkt) AA BB HOST send a packet IP Forwarding Switch IP cache IP Forwarding Switch 3 10/30/2020 Router (ARP_Res) aa rr aa AA rr RR Router port 3 102

ITRI CCL Route Once, Switch Many switching routing IP Forwarding Switch Router Inter-Subnet traffic: Switched rather than Routed CCL/N 300; Paul Huang 10/30/2020 103

ITRI CCL Route Advertisements: RIP and OSPF r. RFC-1388 íSend RIP-1 packets in broadcast mode. íSend RIP-2 packets in multicast mode. r. RFC-2178 íSend OSPF packets in broadcast mode. CCL/N 300; Paul Huang 10/30/2020 104

ITRI CCL IP Learning Process if (a unicast packet && an IP packet) learn (DIP-DA 2) pair and tag proper port ID; else do nothing. IP Forwarding Process if (a unicast packet && DA 2 = router’s MAC address) lookup IP Table (cache) and forward the packet to destination port with proper MAC substitution; else forward the packet to corresponding router port. CCL/N 300; Paul Huang 10/30/2020 105

ITRI CCL Issue of Dynamic Routing ¬IN-BAND route refresh 4 3 2 1 3 IP Forwarding Switch 1 2 Router 4 OUT-BAND route refresh 4 3 2 null 1 IP Forwarding Switch 1 CCL/N 300; Paul Huang 2 3 Router 4 10/30/2020 106

ITRI CCL Cells-in-Frame CCL/N 300; Paul Huang 10/30/2020 107

ITRI CCL Cells-In-Frame Concept Workstation Ethernet-to-ATM CIF Edge Switch Applications Winsock 2. 0 SIG NULL SIG IP CIF NDIS SHIM Driver ATM Functionality (Qo. S / Flow Control over Ethernet ATM Cells over Ethernet Wire Multiple ATM Cells w/ Same VC CCL/N 300; Paul Huang 10/30/2020 ATM Hdr Ethernet Hdr 108

ITRI CCL Cells-In-Frames Reference Model CIF Workstations CIF Switch ATM Workstation Upper Layers SSCS CIF Mapping Function CPCS CIF DLL PHY CCL/N 300; Paul Huang Ethernet CIF SAR DLL ATM PHY CPCS SAR ATM 10/30/2020 ATM PHY 109

ITRI CCL CIF ABR Flow Control RM Cells passed onto Workstation at reduced rates to convey ABR rate to SHIM, TCP, and source CIF Ethernet Switch SHIM uses ABR rate from the RM cells to control the transmission rate for each VC’s queue and then controls TCP to send at the same rate instead of guessing and oscillating CCL/N 300; Paul Huang Switch acts as a source and destination for ABR, turning around the RM cells 10/30/2020 110

ITRI CCL l Functions in CIF Switches Signaling Functions » The CIF switch will appear as a single device with multiple ATM addresses, one for each of the Ethernet attached workstations l Management Functions » The CIF switch will intercept, examine, and forward ILMI messages l Traffic Shaping Functions » The CIF switch will act as a virtual source / virtual destination (VS/VD) on behalf of each workstation CCL/N 300; Paul Huang 10/30/2020 111

ITRI CCL l Stated Advantages of CIF Inexpensive and ubiquitous » Uses existing Ethernet adapters (saves $$) » Large installed Ethernet base (add new ATM software) » Cost (CIF switches) @ Cost (Ethernet switches) l Provides ATM functionality right away. » Guaranteed Qo. S over standard Ethernet » Allows voice over Ethernet (saves $$) » Allows flow / congestion control CCL/N 300; Paul Huang (new services) (better than TCP/IP) 10/30/2020 112

ITRI CCL l Potential Disadvantages of CIF Software SHIM (CIF driver) will hurt performance » No pipelining to optimize performance » Per packet interrupt results in large delays, low throughput l Requires new equipments anyway » New CIF switches are required – CIF switches could be as complicated as ATM switches (requires Qo. S support, WFQ, ILMI, Signaling, P-NNI routing, etc. ), so may not be cheaper than Ethernet switches » Eventually Ethernet adapters and drivers needs to be changed. – Why not go straight to ATM adapters. CCL/N 300; Paul Huang 10/30/2020 113

ITRI CCL LAN Emulation CCL/N 300; Paul Huang 10/30/2020 114

ITRI CCL LAN Emulation Model LE Configuration Server LECS LE Client (LEC) LE Server (LES) ATM Server • Initialization • Registration • Address Resolution ATM Network LE Client (LEC) Broadcast & Unknown Server (BUS) • Data Forwarding Bridge LE Server (LES) Legacy LANs LUNI LE Client (LEC) Broadcast & Unknown Server (BUS) ATM Server CCL/N 300; Paul Huang • Initialization • Registration • Address Resolution • Data Forwarding 10/30/2020 115

ITRI CCL LE Service Components l LE Client (LEC) * provide a MAC level emulated IEEE 802. 3 or 802. 5 service interface l LE Server (LES) * registration * resolving MAC addresses to ATM addresses l Broadcast and Unknown Server (BUS) * send the broadcast MAC address frame * send all multicast traffic * send unicast frames (before data direct VCC has been established) l LE Configuration Server (LECS) * provide configuration information, address of LES CCL/N 300; Paul Huang 10/30/2020 116

ITRI CCL/N 300; Paul Huang LUNI Protocol Overview l Initialization l Configuration l Joining l Registration and BUS Initialization l Data Movement 10/30/2020 117

ITRI CCL/N 300; Paul Huang Initialization l Must determine the ATM address of the LECS l Use SNMP ILMI to get address from a table in the switch and place call to that address l Use well-known ATM address l If that fails, use the VPI/VCI 0/17 PVC as the connection to the LECS l If LECS is not available, try the LES 10/30/2020 118

ITRI CCL Configuration · LEC provides: » ATM address » MAC address » LAN types and frame sizes requested · LECS returns: » LES address » LAN type and frame size to use CCL/N 300; Paul Huang 10/30/2020 119

ITRI CCL Joining l Create Control Direct bi-directional VCC l Transmit Join Request (ATM address, LAN info, proxy indication, optional MAC address) l Possibly accept Control Distribute VCC before Join Response is received l May timeout or fail CCL/N 300; Paul Huang 10/30/2020 120

ITRI CCL Registration and BUS Initialization l Register any MAC addresses l Resolve 0 xffffff MAC address to get ATM address of BUS l Create bi-directional Multicast Send VCC to BUS l Accept unidirectional Multicast Forward VCC from BUS CCL/N 300; Paul Huang 10/30/2020 121

ITRI CCL Data Movement l When a data frame is available for transmission, check internal cache l If unknown, ask the LES l While waiting for response, any transmit frame(s) via BUS l Establish direct connection when response is received CCL/N 300; Paul Huang 10/30/2020 122

ITRI CCL LEC Connections across LUNI Workstation LEC Config Direct VCC Control Direct VCC Config Direct VCC LECS Bridge LEC Control Direct VCC LES Control Distribute VCC Multicast Send VCC BUS Multicast Forward VCC Legacy LAN Data Direct VCC CCL/N 300; Paul Huang 10/30/2020 123

ITRI CCL Address Resolution Frames l IP_ARP frames (RFC 826, Nov. 1982) IP --> 48 -bit MAC address l LE_ARP frames (ATM-Forum/LAN emulation over ATM Spec) 48 -bit MAC address --> 20 -byte ATM address l ATM_ARP frames (RFC 1577, Jan. 1994) IP --> 20 -byte ATM address CCL/N 300; Paul Huang 10/30/2020 124

ITRI CCL LE_ARP Flow LES LEC 1 2 A 1, 4 3, 5 Network 3, 5 LEC 2 1 B BUS 1. LEC 2 sends and LE-ARP request to find ATM addr of MAC A via Control Direct VCC 2. LES does not find the corresponding ATM address of MAC A in the REG-DB 3. LES sends the LE-ARP request to all Proxies via PROXY-DB 4. Upon receiving the LE-ARP request, LEC 1 looks for its filtering table to find MAC A. LEC 1 sends back the LE-ARP response with ATM LEC 1 5. LES sends the LE-ARP response to LEC 2 via LECID-DB CCL/N 300; Paul Huang 10/30/2020 125

ITRI CCL Message Flow / ATM to ATM LES 4 a, 4 b IP A MAC A ATM A 1 ES A 3 a, 3 b 2, 4 3 BUS 3 c 2, 4 ES B 3 IP B MAC B ATM B Control direct VCC Multicast send VCC Multicast forward VCC Signalling Data direct VCC 5, 4 c /* to find MAC B */ 1. ES A sends an IP-ARP request, looking for MAC B 2. ES A sends the IP-ARP request to ES B, via BUS-ES B 3. ES B sends the IP-ARP response to ES A, via BUS-ES A ------------------------------------/* to find ATM addr of MAC A */ 3 a ES B sends LE-ARP request to find ATM addr of MAC A 3 b. LES sends the LE-ARP response to ES B 3 c. ES B sets up a direct VCC to ES A CCL/N 300; Paul Huang ------------------------------------4. ES A begins to transfer data to ES B, via BUS /* to find ATM addr of MAC B */ 4 a. ES A sends an LE-ARP request to find ATM addr of MAC B 4 b. LES sends the LE-ARP response to ES A 4 c. ES A knew it has a direct VCC to ES B. Before using it, ES A sends a flush message to ES B --------------------------------------5. After ES A receives the ack of flush message, the data flow is ES A-ATM network-ES B 10/30/2020 126